Because you haven't imported the Vector type, there will be a vaguely familiar symbol in the left margin, a red box with an "x" combined with a yellow light bulb.

因为您尚未导入vector类，这时在左边框中就会出现一个似曾相识的符号，即一个带叉“X”的红框，再加上一个黄色的灯泡。

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The theory of moral vector can shed light on moral education .

道德矢量论对道德教育有着诸多重要的启示。

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Since you haven't imported the Vector type, there will be a symbol in the left margin, a red box with an "x" combined with a yellow light bulb, as shown in Figure 4.

因为没有导入Vector类型，所以左侧空白上将有一个符号，是一个包含“X”和黄色电灯泡的红色方框。(参见图4。)

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So if HTML5 is more suitable for light interface enhancements, this leaves rooms for Flash to do what it does best: heavy interface enhancements, vector-based animations, advanced video and audio features, and immersive environments.

FORBES: Why Opposing HTML5 And Flash Is Nonsense