They were surprised that a child should work out the problem____ they themselves could not.

Mary and I have been close friends ______ we met each other 10 years ago.

Our society insists on regular habits, timekeeping and punctuality, and whether we like it or not, ______ we mean to make our way in society, we have to comply ( to act in accordance with a demand, rule, etc.) its demands.

_______ the calculation is right, scientists can never be sure that they have included all variables and modeled them accurately. 

I’d love to stay in the community        I grew up, but ambition can drive me to the city to be “      the big companies are”.

You are saying that everyone is equal, which is ________ I can’t agree more.

--- Are your family ready for rafting?
---Yes, I really want my children to experience that       they are young. 

A man does not know the difficulty of anything _______ he does it personally.

________ advertisements are of great help, I don’t think we should entirely rely on them.

--Did you remember to give Jerry the money?
--Yes. ________ I saw her, I’m sure.