试题题干
Translate the following sentence into Chinese.
Enough experiments have been done to decide that homing pigeons (and maybe other birds) seem to have a build-in clock.
参考答案
试题解析
考点：enough experiment足够的实验；homing pigeon信鸽；seem to似乎；a build-in clock一个内在的时钟。
句子结构：主句为Enough experiments have been done，to decide···为目的状语。