学生们经常在校园的四方院里野餐。

Students often have picnics on the ___quad of the campus.

这对夫妇惊讶地发现他们怀上了四胞胎。

The couple were surprised to learn they were expecting a ___quad.

深蹲可以很好地锻炼大腿前侧的股四头肌。

Squats are great for strengthening your ___quad muscles.