…. , they would not have had such a successful conference
A.Due to good preparations
B.But for they had had good
C.Without good preparations
D.If their good preparations

Call your parents…. they will start to worry.
A.if only
B.otherwise
C.if so
D.in case

If it.... for the life jacket, I would have drowned.
A.is not
B.was not
C.has not been
D.had not been

.... heavy traffic, we would not have been late for the train.
A.If
B.If only
C.Supposed
D.But for

.... the boat leaves on time, we will arrive in Paris by the morning.
A.If only
B.Provided that
C.But for
D.Without

Try harder.... you will lose everything you have.
A.provided that
B.supposing that
C.if
D.unless

We will be holding a meeting this afternoon to decide _________ needs to be revised before the report goes to print.
A.what
B.those
C.whether
D.there

For those who have made an investment, _________ happens during the first year is an important indicator of how successful the company will be.
A.that
B.as
C.what
D.how

.... he arrives soon, we will have to start the conference without him.
A.Suppose
B.Provided
C.Unless
D.If

.... more carefully, he would not have had the accident yesterday.
A.If Peter drove
B.Had Peter driven
C.Only if Peter could drive
D.Unless Peter had driven