由于新的恐怖威胁，周年日戒备森严。街道被封闭。人行道上警察林立。
Security was tight because of a new terrorist threat. Streets were closed. Police lined the sidewalks.
不过，我猜当时根本就没有什么别的选择，因为人行道被封闭了，他们当时正在维修。
But I guess there wasn't really much of an alternative, because the sidewalk was closed and they were doing construction work.
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