I don't know how to say it in english How to do

I don't know how to say it in english How to do
I don't know how to say it in english How to do

I don't know how to say it in english How to do
1、to visit 2、educative 3、to write 4、discussion 5、successful 6、to help
7、famous 8、lucky 9、sitting 10、mainly 11、to meet 12、becoming 13、meaningless
14、to study 15、luckily 16、unluckily 17、to go 18、making
Ps：11题实在看不到后面,通过句意理解应该是：昨天我在大街上偶遇了老同学.所以用happened to meet