If / Unless: Conditions for Desirable Outcomes

If / Unless

Expressing conditions for desirable outcomes

If / Unless

IF	UNLESS
If – in this condition (one of many) – indicates a condition to achieve a desired outcome.	Unless (if not) –introduces the likely outcome if failing to do the action in the main clause.
You will have a tender turkey if you cook your turkey like this. (Standard word order: X will result if a condition is met.) If you cook your turkey like this, you will have a tender turkey. (Emphasis word order – use a comma: If this condition is met, X will result.)	You will have a tough turkey unless you cook your turkey like this. (Standard word order: X will result if a condition is not met.) Unless you cook your turkey like this, you will have a tough turkey. (Emphasis word order: If this condition is not met, X will result.)

UNLESS

If – in this condition (one of many) – indicates a condition to achieve a desired outcome.

Unless (if not) –introduces the likely outcome if failing to do the action in the main clause.

You will have a tender turkey if you cook your turkey like this.
(Standard word order: X will result if a condition is met.)

If you cook your turkey like this, you will have a tender turkey.
(Emphasis word order – use a comma: If this condition is met, X will result.)

You will have a tough turkey unless you cook your turkey like this.
(Standard word order: X will result if a condition is not met.)

Unless you cook your turkey like this, you will have a tough turkey.
(Emphasis word order: If this condition is not met, X will result.)

Only if / Otherwise

ONLY IF	OTHERWISE
Only if – under this condition – emphasizes the one, specific condition to achieve the desired outcome. Emphasis-word-order requires the subject to switch positions with the auxilliary verb.	Otherwise – if not – indicates the likely outcome if you do the opposite action from the one indicated in the sentence before it.
You will have a delicious dinner only if you cook your turkey like this. (Standard word order: X will result under this condition.) Only if you cook your turkey like this, will you have a delicious dinner. (Emphasis word order – subject -auxillary verb changes word order, use a comma: Under this condition, X will result.)	Cook your turkey like this. Otherwise, you will have a tough turkey. (Standard word order only)

ONLY IF

OTHERWISE

Only if – under this condition – emphasizes the one, specific condition to achieve the desired outcome. Emphasis-word-order requires the subject to switch positions with the auxilliary verb.

Otherwise – if not – indicates the likely outcome if you do the opposite action from the one indicated in the sentence before it.

You will have a delicious dinner only if you cook your turkey like this.
(Standard word order: X will result under this condition.)

Only if you cook your turkey like this, will you have a delicious dinner.
(Emphasis word order – subject -auxillary verb changes word order, use a comma: Under this condition, X will result.)

Cook your turkey like this. Otherwise, you will have a tough turkey.
(Standard word order only)

if this condition is met = under this condition

Condition & Result Phrasing

CONDITION	RESULTING ACTION
If you use a thermometer, This is one way to tell when it's ready. There may be other ways as well.	you will know when your turkey is done.
Only if you use a thermometer, There is only one way to tell when it's done. (Specifically, use this way.)	will you know when your turkey is done.
Provided that you use a thermometer, There is only one way to tell when it's done. (Specifically, use this way.)	you will know when your turkey is done.
Unless you use a thermometer, Not using a thermometer will give bad results. (Listen to me!)	you won't know when your turkey is done.
Use a thermometer.	Otherwise, you won't know when your turkey is done. Not using a thermometer will give bad results. (Using other ways is unsatisfactory!)
Use a thermometer,	or else you won't know when your turkey is done. Not using a thermometer will give bad results. (Using other ways is unsatisfactory!)

Note: Sometimes, using the negative form is a way for the speaker to impose his/her will. Compare: "Are you tired?" and "Aren't you tired?". The speaker, when using the negative, wants the listener to agree.

Only If

Word Order – Transposition

Only IF (at the beginning of the sentence)

CONDITION		RESULTING ACTION
Conjunction	Condition (followed by a comma)	Outcome – the auxiliary verb moves in front of the subject.
If	you dry your dishes with a towel,	they will be spotless!
Only if	you dry your dishes with a towel,	will they be spotless!
If	you use Zing dish soap,	you get really clean dishes.
Only if	you use Zing dish soap,	do you get really clean dishes. (get = do get)
If	you used Zing dish soap,	you got really clean dishes. (got = did get)
Only if	you used Zing dish soap,	did you get really clean dishes.

Note: If there is no auxiliary verb , you will need to add one.

Only if vs. If only

ONLY IF	IF ONLY
Us only if to indicate the one condition required to achieve a desired effect. (under one condition) When used at the beginning of the sentence the auxiliary verb is moved before the subject.	Use if only to express a wish – one that you are doubtful about actually happening. The result clause is optional and is separate. It is more emphatic than I wish…
Only if you dry your dishes with a towel, will they be spotless!	If only I had more time! ( I could relax.)
Only if you clean up your room, will you find your lost jeans.	If only you would clean up your room. You would find your lost jeans.
Your windows will be clean enough to see your face only if you wash them with Zing!	If only I had some Zing window cleaner.
I will please my mother-in-law only if my house is clean.	If only I could please my mother-in-law. (past)
I am happy only if you are here. / Only if you are here, am I happy.	If only you were here!
She was pleasant only if we told her what she wanted to hear.	If only he hadn't told his mother everything. (past)

Also see Wishes (only if)

Even if & Whether or not

EVEN IF	WHETHER OR NOT
without condition; used before a negative condition or verb	without condition; used with a positive verb
I'll help you even if I don't have much time.	I'll help you whether or not I have much time.
I like to walk to work even if it is raining. (negative context - bad weather)	I like to walk to work whether or not it is raining.
Even if your father doesn't say it, he loves you.	Whether or not your father says it, he loves you.

Also see even if Adverbs of Emphasis

Practice

Road Rules

Select the answer that best completes the sentence.
Then, check your answer by clicking the check button to the right.

More than one answer may be correct.
Note the punctuation (which affects the meaning of the sentence.)

#	YOUR RESPONSE	OPTIONS
1.	Most drivers will let you change lanes you signal well in advance.
2.	You shouldn't change lanes you signal first.
3.	A driver may change lanes it is safe to do so.
4.	A driver should stop and check for oncoming traffic before making a right turn on a red light; , he will cause an accident.
5.	A driver may make a right turn on a red light it is a one-way street and the traffic is oncoming.
6.	A driver can go through a red light a police officer signals the driver to do so.
7.	A driver may drive 65 mph in a zone that is marked 65 mph it is unsafe to do so.
8.	Drivers must be careful; , accidents will happen.
9.	you put your full attention on driving, will you lower your chances of having an accident.
10	A driver should park in a handicapped space the driver has a special permit.
11.	When parking, a driver should park between the marked lines. , he will take up two spaces.
12.	A driver should look carefully before opening his door on the traffic side of the street, oncoming traffic may hit the door.

Grammar-Quizzes.com

PRACTICE ON POINTS OF ENGLISH GRAMMAR

Conditionals

If / Unless

Expressing conditions for desirable outcomes

If / Unless

Only if / Otherwise

Condition & Result Phrasing

Only If

Word Order – Transposition

Only IF (at the beginning of the sentence)

Only if vs. If only

Even if & Whether or not

Practice

Road Rules