I couldn't understand（ ） the baby alone.

I couldn't understand（ ） the baby alone. I couldn't understand the people.They talked fast.（合并为一句） You couldn\'t understand what I said? I couldn’t understand why he pretended _________ in the book I couldn’t understand why he pretended ____ in the bookstore I can't understand ( ) the boy alone last night. A.why she l What he said c_____me.And I couldn't understand him. _____,I couldn't understand what he said Baby.I think i can't understand your ____ his mother,the baby couldn't help laughing baby i need you Don't leave me a alone I can not understand （ ）the boy alone?A why she left B why d