The picture shows us _______ in Nanjing in the past.

I rang you at about ten o’clock, but there was no reply. – Oh, that was probably ________ I was seeing the doctor.

During the reconstruction of the city , many modern tall building went up old shabby houses were torn down.

______is very important for us to learn English well.

I have finished my homework already, mum.— When ________ you ________ it?