Question

1. I'm sorry I missed Professor Baker's lecture.

I'm sorry not..................

2. We may not be able to give the concert.

the concert...............

3. I was not surprised to hear that Harry had failed his driving test.

It came.....................

4. We'd better leave them a note, because it's possible they will arrive later. ( case )

5. Before he came here, he worked for Mr. Smith. ( previous)

Answer 1

1. I'm sorry I missed Professor Baker's lecture.

I'm sorry not to have heard/ attended Profressor Baker's letter.
..................

2. We may not be able to give the concert.

the concert

.....The concert may have to be cancelled...........

3. I was not surprised to hear that Harry had failed his driving test.

It came...as no surprise ( to me ) that Harry had failed his driving test...................

4. We'd better leave them a note, because it's possible they will arrive later. ( case )

We'd better leave them a note in case they arrive later.

5. Before he came here, he worked for Mr. Smith. ( previous)

Before he came here, his previous boss/ employer was Mr. Smith.

Answer 2

1. I'm sorry I missed Professor Baker's lecture.

I'm sorry not to have attended Profressor Baker's lecture.

2. We may not be able to give the concert.

The concert may have to be cancelled.

3. I was not surprised to hear that Harry had failed his driving test.

It came as no surprise to me that Harry had failed his driving test.

4. We'd better leave them a note, because it's possible they will arrive later. ( case )

-> We'd better leave them a note in case they arrive later.

5. Before he came here, he worked for Mr. Smith. ( previous)

-> Before he came here, his previous employer was Mr. Smith.