Not "I fly to London next Tuesday." — say "I'm flying to London next Tuesday.". 说已经安排好的计划，用 am/is/are 加 -ing：I'm flying。
试一试: He ___ his new job next Monday. (is starting / starts / start) 答案: is starting — 下周一开始新工作是已经安排好的计划，所以用 is 加 -ing 形式：He is starting.（他要开始新工作了。）“Starts” 用于习惯或时刻表，“start” 又漏掉了 is。
不打算做的计划
说不打算做的计划，把 not 放在 am、is、are 后面：'m not、isn't、aren't 加 -ing 形式。
We're not working on Friday afternoon.
She isn't coming to the party tonight.
I'm not meeting them tomorrow.
Not "We don't working on Friday." — say "We're not working on Friday.". not 放在 are 后面：we aren't working，绝不是 we don't working。
试一试: Sorry, we ___ on Friday afternoon, the office is closed. (aren't working / don't working / not working) 答案: aren't working — not 放在 are 后面：we aren't working.（我们不上班。）“Don't working” 用错了助动词，“not working” 又漏掉了 are。
问计划
问计划，把 am、is、are 放在主语前面。想问细节，就在开头加疑问词，比如 what 或 where。
Are you leaving tomorrow?
Is Mei coming to the party tonight?
What time are you leaving?
Where are we meeting them?
Not "You are leaving tomorrow?" — say "Are you leaving tomorrow?". 提问时把 are 放在 you 前面：Are you leaving?
试一试: ___ Mei coming to the party tonight? (Is / Does / Will) 答案: Is — 问已安排好的计划，用 is 加 -ing 形式：Is Mei coming?（Mei 会来吗？）“Does Mei come” 问的是习惯，“Will Mei come” 是另一种说将来的方式，不是这种已安排好的计划句型。
试一试: Amina ___ Lars tomorrow, but she ___ him on Friday. (is meeting … isn't seeing / meets … doesn't see / is meeting … doesn't see) 答案: is meeting … isn't seeing — 两句都是已经安排好的计划，所以都用 is 加 -ing 形式：she is meeting Lars，还有 she isn't seeing him on Friday。一般现在时（meets、sees）用于习惯，不是这种已安排好的计划。