我不敢想如果我们没系安全带会发生什么。

___I ___dread ___to ___think what could have happened if we hadn't been wearing seat belts.

我不敢想自从我弟弟把它落在公园那天起，它发生了什么。

___I ___dread ___to ___think what has happened to it since the day my younger brother left it in a park.

我不敢想如果我们现在不采取行动，地球的未来会怎样。

___I ___dread ___to ___think what the future holds for our planet if we don't act now.