希腊字母表的第一个字母是阿尔法。

The first letter in the Greek alphabet is ___alpha.

这个项目还处于alpha测试阶段，尚未向公众开放。

This project is still in the ___alpha testing phase and not open to the public yet.

猴群总是听从那只最强壮的阿尔法猴的指挥。

The monkey troop always follows the commands of the strongest ___alpha male.

天狼星是大犬座中最亮的恒星。

Sirius is the ___alpha star in the constellation Canis Major.