1 to go wherever they choose 中，wherever they choose为融合型关系分句作状语。其中they choose为所谓的自由选择结构（free choice construction），这种结构中的动词choose，want，like，wish，please后隐含一个省略了的不定式。本句中wherever they choose=wherever they choose to go. 即wherever其实是省略了的不定式to go的状语，而不是choose的宾语。所以句子是没有问题的。
关于自由选择结构，你可以参读剑桥英语语法p1075. 我将有关内容粘贴如下：
The free choice construction (You can do whatever/what you want)
[23] i Invite [whoever/whomever/who/whom you like].
ii Liz can go [wherever/where she wants].
In fused relatives like these the referent of the (overt or understood) subject of the matrix
clause is given the freedom to choose: in [i] it is for you to decide who you invite, and in
[ii] it is for Liz to choose where she goes. We have used ‘free choice’ to label one sense of
any, and constructions with any + integrated relative are very close in meaning to the
above: compare Invite anyone you like and Liz can go anywhere she wants (but see Ch. 5,
§7.14, n. 32, for a slight difference).
There is no detectable difference in meaning between the ·ever and simple forms in
this construction, and since who, which, and how can hardly occur in other kinds of fused
relative, it is plausible to see the ·ever as here omissible by virtue of being redundant: the
“any whatever” meaning is entailed by the free choice and does not have to be explicitly
expressed in the relative word. The verb in this construction belongs to a small class
consisting primarily of choose, like, please, want, wish, and is interpreted as if it had a
clausal complement – e.g. for [ii] “She can go wherever she wants to go”. Note, then, that
Sack who you like does not mean “Sack the persons that you like”, but “Sack whoever
you care to sack”. However, the distinctive syntactic property of the construction – that
of allowing certain simple forms which do not normally occur in fused relatives – is
generally restricted to the case where the clausal complement is merely implicit, so that
we have Invite who you want, but hardly ?
Invite who you want to invite. Moreover, please
does not in fact license clausal complements: Go where you please, but not, in Present
day English, ∗
He pleased to go to Paris. And with like the meaning differs aspectually
from that of a construction with an infinitival complement. I like to take the biggest
portion, for example, implies repeated taking (cf. Ch. 14, §5.6.1), whereas Take which you
like does not. There are also constraints on the matrix clause. For example, the fused
relative must follow the matrix verb: I’ll invite who you like but not ∗
Who you like I’ll
invite.
2 sealing前应该有逗号，这是现在分词短语作结果状语，分词的逻辑主语为前面分句的内容。as介词短语为sealing的宾补。其中to be为不及物动词作定语修饰place，为动状关系。
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