We know that about seventy percent _____ the earth _____ covered by water.
The mother walked into the room in order not to wake up her baby.
I like English very much. I never miss a to practice English with foreigners.
— Who helped Li Lei with his English? — , he learnt it by himself.
My school is different theirs. It has many after school clubs.
I didn’t understand ______, so I raised my hand to ask.