如图，t＝0时刻，波源在坐标原点从平衡位置沿y轴正向开始振动，振动周期为0.4 s，在同一均匀介质中形成沿x轴正、负两方向传播的简谐横波．下图中能够正确表示t＝0.6 s时波形的图是
There are ________ flowers around my school.A．much B．lot C．many
The desk is ________ front of the chair.A．on B．in C．at
Look at the photo ________ my sister.A．of B．and C．by
We ________ about tongue twisters last Monday.A．learn B．learned C．leaning
Amy ________ pictures with colour pens last evening.A．drew B．draw C．drawed
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