My sister is only four years old, but she can look after ________ now.

My mother becomes more and more forgetful. She searched for her cell phone for a whole day last Sunday but it ______ in her coat pocket the next day. [ ]

en the boy playing by the river fellinto the river, I was out of the room _______.

Since 2012, when he _______, the soldier has been in the army.

This kind of animals has nearly _____ because theirhomelands are gone.