Bob promises to join in the football match ________ hehas to help his parents on the farm.

（湖南）说着，进入石洞来，只见佳木茏葱，奇花熌灼，一带清流，从花木深处曲折泻于石隙之下。 ，皆隐于山坳树影之间。俯而视之，则清溪泻雪，石磴穿云，白石为栏，环抱为沿，石桥三港，兽面衔吐。桥上有亭。下列语句填入语段中划横线处，衔接最恰当的一项是（ ）

ildren went home from thegrammar school, their lessons ______ for the day

It’s very kind_______you to buy an airticket________Singapore for me．

It is easy to be grateful for the good things, ______ a life of rich fulfillment comes to those who are also thankful for the setbacks