1) Why they left their hometown for Yunnan
　　(考点：主语从句)

　　2) What confused me most
　　(考点：同上)

　　3) That this was done on purpose
　　(考点：同上)

　　4) who should be responsible for this matter
　　(考点：较长的主语从句可以后置，用it作形式主语)

　　5) whom Mary is engaged to
　　(考点：同上)

　　6) what can be done today
　　(考点：宾语从句)

　　7) what I have been looking for
　　(考点：表语从句)

　　8) whether/if robots will one day have vision as good as human vision
　　(考点：whether/if引导后置的主语从句)

　　9) Whether she likes the present
　　(考点：whether引导前置的主语从句)

　　10) whether I should ask for another loan
　　(考点：whether引导表语从句)

　　11) whether they will support us
　　(考点：whether引导宾语从句)

　　12) whether I can count on your vote
　　(考点：whether引导同位语从句)
　　(9-12中的whether不可以替换为if)

　　13) that the Government could do nothing to raise their wages
　　(考点：同位语从句)

　　14) that the chairman would agree to this proposal
　　(考点：同上)