可以, 但很少!1) Professional can (两个动词) your burden to a great extent when there is a need of air repair.2) stomach pain....3) I that she is married.4) He to USA.
可以，一般用and or 等连接词连接。比如Give me your hand and hold me.
be动词可以和其他动词连用，如i am going to school
