Conditionals without 'if'

1. Although 'if' is the most common word used, other expressions may be used in conditional clauses

Whether: expresses an alternative; with whether we can use 'or not' immediately after or in end position; whether is also used before a verb in infinitive

• I called Paul to find out whether or not he really said that
• I called Paul to find out whether he really said that or not
• I was wondering whether to go for a swim

Accepting (that) / Given (that): both give more degree of certainty than 'if'

• Accepting that Mary just won the lottery, she doesn't seem very happy
• Given that he just arrived from a long flight, don't you think he'll want to sleep more?

Assuming (that): implies an almost true situation

• Assuming that he knows the answer, we should ask him

In case: gives a reason to a previous action

• I'll buy an umbrella in case it rains

Otherwise: means 'except for what was just referred to'

• I like going to bed early; otherwise I'm tired the next day

Supposing: suggests an act of imagination

• Supposing he finishes his project today, how will we able to present it tomorrow?

As/so long as / Providing / Provided (that) / On condition (that): suggest a condition imposed by the speaker

• I will tell you as/so long as you don't tell anyone
• You can stay with us providing you do some work
• I will go to the party, provided that I am invited
• She accepted the job on condition that there would be opportunity for advancement

Unless: an alternative to 'if ... not'

• I'm going to the beach tomorrow if it does not rain / I'm going to the beach tomorrow unless it rains