(2013·湖南省重点中学3月联考)We pursue happiness，thinking one day we will find it.But_________it by seeking it.

19．_____ your advice, I’m sure to consider it and give you reply in time

The man we followed suddenly stopped and looked as if ________ whether he was going in the right direction.[ ]

When was China’s first cargo spacecraft, Tianzhou 1 sent into space successfully— April 20.

We won’t give up __________ we should fail 10 times