()many times,but he still could not understand it.
()many times,but he still could not understand it.
______ many times,he still could not understand it.
___ many times but he still could not understand it.(tell)
____ many times but he still couldn't understand it
( )many times, but he still could not rem
___ ,but he still could not understand it
____ but he still could not understand it.
1.___many times,but he still couldn't understand it.
_____scores of times,but he still couldn't understand it.
________many times,but he still couldn't understand it.
I told him many times but he failed ( )(understand)it.
—— many times,I still could not understand how to operate th