I forgot to take the key to the bike with me again.

When she saw me, she did’t stop. She just walked _____.[ ]

There are two dogs in my family. One is white,_____________ black.

You should learn English by using it.—What ____useful advice! Thank you very much.

It was _______ great fun to be a host, wasn’t?－Yes. That’s _______ experience hard to forget.