用所给单词的适当形式填空。
(1). It was ______. There was a lot of ______(rain).
(2). It was ______. There were black ______(cloud) in the sky.
(3). Children ______(go) to the park by bike this Sunday. 
(4). We ______(see) some bees flying in the flowers just now.
(5). It ______(rain) all day on 20^th September.
(6). He ______(look) sad, because he ______(lose) a new pen.