15. Fill in: can, can't, couldn't have to haven't been able to, should, need to, must or must have.
Dear Mum and Dad, Here I am in my new flat. Sorry I haven't been able to couldn't write earlier, but, of course, I was busy moving in and unpacking.
1. Now, I just buy curtains and a few rugs to make the flat really homely.
2. When I unpacked, I find my toaster anywhere.
3. 1 left it behind in the old flat!
4. I'll come to see you on Sunday 14th. I bring my flat mate?
5. If we set off early, we arrive in time for lunch.
6.1 wait to eat your delicious apple pie!
7. Anyway, 1 go now.
8. There's someone at the door. It be the plumber; he is going to install the washing machine. See you on Sunday. Love, Judy

1. Now, I just need to buy curtains and a few rugs to make the flat really homely. (должен купить)
Explanation: The phrase "I just need to" indicates that the speaker has a requirement or obligation to purchase curtains and rugs.

2. When I unpacked, I couldn't find my toaster anywhere. (не смог)
Explanation: The word "couldn't" suggests that the speaker was unable to find their toaster despite searching for it.

3. I left it behind in the old flat! (должен был)
Explanation: The phrase "I left it behind" suggests that the speaker unintentionally left their toaster in the old flat. The use of "had to" would not be appropriate in this context, as it implies a necessity rather than an oversight.

4. I'll come to see you on Sunday 14th. Can I bring my flatmate? (могу)
Explanation: The use of "can" indicates that the speaker has the ability or permission to bring their flatmate along when visiting their parents.

5. If we set off early, we must arrive in time for lunch. (должны)
Explanation: The use of "must" suggests a strong obligation or necessity. In this context, it implies that if the speaker and their flatmate leave early, they should be able to arrive in time for lunch.

6. I can't wait to eat your delicious apple pie! (не могу)
Explanation: The use of "can't" indicates that the speaker is very eager or excited to eat their parent's apple pie. It implies a strong desire or anticipation.

7. Anyway, I have to/Could I go now. (должен/могу)
Explanation: The use of "have to" indicates a necessity or obligation to leave. Alternatively, "could I" suggests a polite request for permission to leave.

8. There's someone at the door. It must be the plumber; he is going to install the washing machine. See you on Sunday. (должно быть)
Explanation: The use of "must" suggests a strong likelihood or probability that the person at the door is the plumber, who has been hired to install the washing machine.