A:山脊、陡崖、山谷、山顶
B:山谷、鞍部、山脊、陡崖
C:山脊、山谷、鞍部、陡崖
D:山谷、鞍部、山脊、盆地
对动脉的叙述中,不正确的是( )
根据氢原子和氟原子的核外电子排布,对F2和HF分子中形成的共价键描述正确的是( )
A:Good morning.
B:____
A:I am Li Fei.____
B:My name is Wang Qiang.
A:____
B:Yes,I am.
A:I am twelve.____
B:I am twelve too.
B:OK! Let's go.
A.Good idea!
B.How are you?
C.Good morning.
D.What about you?
E.What's your name?
F.Are you from Beijing?
G.Let's go and play football.