How do you spell ruler —_______.

Have you heard of Zhai Mo______became the first Chinese person to travel around the world in a sailboat?

Do you know our town ? —-No ,this is the first time I _____here

Many a _____ about the poor services of the airline nowadays. [ ]

It’s certain that we are ________ to having a clean and beautiful home in the future because some special projects are ________ to protect the environment.