–What does your grandma often do after supper?--She ___ for a walk.

 My friend Li Xiao knows my hometown very well because he _______ there many times with me.

Please come to my party if you ____ free tomorrow.

There _______ less air pollution in the country .

---Excuse me. You shouldn’t smoke here. Look at the sign “NO SMOKING HERE”.--Sorry, I ________ it just now.