He is very humorous, while his brother is rather seriousThat is ___their difference lies

ow long hactually．I’m on a big journey, you know．I ______all the places ofinterest here．

We expected you yesterday. — I’m sorry, I you to say that I couldn’t be here until today. [ ]

.Most business letters and governmentreports are the main situations _________ formal language is used. ^*

He is so busy. He cannot afford enough time with his son ______ he wants to.