根据句意和汉语注释，写出单词的正确形式。
Obama, one of the ________________(总统) of the United States, visited China in 2009.
Lily often does well in the drawing ____________(竞赛). She is interested in taking part in them.
I’ll ________________(到达) the supermarket at 5.00 p.m. if there isn’t much traffic.
Please read all the _________________(指示) before you start to do the work.