若：Yesterday,we went to the USA and I (see)a lot of flours.
追答这里and 是个连词，连接的是两个并列的谓语成份，所以前面和后面的动词都要用同一时态形式
Yesterday,we went to the USA and I (saw)a lot of flours.
这里and 是个连词，连接的是两个并列的谓语成份，所以前面和后面的动词都要用同一时态形式
Yesterday,we went to the USA and I (saw)a lot of flours.