Answer:
What he (meant) is not clear to me.
9. They (work) hard when they (have) to.
I (do not remember) his name, but I (think) my
brother will be able to tell you.
11. The exercise we (are going to do) now (appears) to be easy
but it (contains) some tricky sentences.
12. Now that you have given me an example I (can see)
Step-by-step explanation: