①是自尊自信的应有表现
②是自立自强的必然选择
③是走向成熟的重要标志
④是可有可无的
A:①②
B:①②③④
C:③④
D:①②③
若把代数式x2﹣2x+3化为(x﹣m)2+k形式,其中m,k为常数,结果为( )
读句子,将问句和答句连线。
①Whose dress is it? ____ A. It's pink.
②What colour is the shirt? ____ B. It's under the sofa.
③Is this your shirt, Dad? ____ C. No, it isn't.
④Where's my hat? ____ D. It's my sister's.