My mom is always bad-tempered when I leave my room untidy.
Giải chi tiết:
bad-tempered = easily annoyed or irritated : dễ dàng tức giận, phát cáu
Around 150 B.C. the Greek astronomer Hipparchus developed a system to classify stars according to brightness.
Biogas can be utilized for electricity production, cooking, space heating, water heating and process heating.