59.B。考查连问问义辨析。句意同上。根起句意，选B
60.D。考查名词词义辩析。根据全文内容，可知attitude符合语境，故远D
61，in。考查介词。短语动词exist in意为“在于”，故填in.
62.located，考查形容词。在句中作hutongs的后置定语，故填located
63.which。考查关系词。先行i词为residence，且介词提前，故填which。
64.development.。考查名词。根据空前的the，填development.
65.significant。考查形答词。根据空后的aspect可知，缺定语，故填significant。
66.have been preserved..考查谓语。根据句中状语since then可知，用完成时，且主谓之间为被动，故填have been preserved.
67.it，考查代词，t在句中作形式宾语。故填it
68.Therefore。考查刷同。根据前后的逻辑关系，填herefore。
69.s。考查主谓一致。动名词短语作主语，用单数。故填is。
70.to strengthen。考查不定式的复合结构表日的，故填to strengthen.

【参考范文】
Dear astronauts.
I'm writing with great excitement to tell you how proud I am for your remarkable accomplishments made in China's space expeditions.
With my curiosity about your life and work in Tiangong Space Station,I am writing to enquire about your current situation.Have you adapted to the weightless environment？If you miss your families.is it possible for you to make video calls on a regular basis？Additionally,impressed by your interaction with us students in
"Tiangong Class".I cannot help admiring your pioneering work,wondering what it takes to be a qualified astronaut.
Wish you a successful mission and a comfortable journey！
Yours faithfully,

                                             Li Hua