algae

池塘里的藻类是鱼类的重要食物来源。

The ___algae in the pond serve as an important food source for fish.

池塘表面覆盖着一层绿色的藻类。

The pond surface is covered with a layer of green ___algae.

科学家在显微镜下观察到了微小的藻类。

Scientists observed tiny ___algae under the microscope.