Hopefully, you've managed to get a good grasp of how grammar works in Japanese and how to use them to communicate your thoughts in the Japanese way. In this final section, we'll be covering some left-over grammar that I couldn't fit into a larger category.
This is a grammar I learned out of a book and was surprised to actually hear it used in real life on a number of occasions. You use this grammar when you think one thing, but much to your astonishment, things actually turn out to be very different. You use it in the same way as you would express any thoughts, by using the quotation 「と」 and 「思う」. The only difference is that you use 「思いきや」 instead of 「思う」. There is no tense in 「思いきや」, or rather, since the results already went against your expectations, the original thought is implicitly understood to be past tense.
This rather formal and seldom-used grammar is used to indicate that two actions were done at the same time. The nuance is a bit difference from 「ながら」 in that some or all of the time spent on doing one action was also used to do another action as an aside. Remember, 「ながら」 is used to describe two exactly concurrent actions.
The interesting thing about this grammar is that no verb is required. You can just attach it a noun, and the verb "to do" is inferred. For instance, "while taking a stroll" can simply be expressed as 「散歩がてら」. In the case where you want to employ a different verb, you also have the option of attaching 「がてら」 to the stem similar to the 「ながら」 usage. In addition, the verb or noun that is accompanied by 「がてら」 is the main action while the following action is the one done on the side.
「あげく」 is a grammar used to describe a result, usually negative, that came about after a great deal of effort. The rule for this grammar is very simple. You modify the verb or noun that was carried out with 「あげく」 and then describe the final result that came about from that verb or noun. Because this grammar is used to describe a result from an action already completed, it is used with the past tense of the verb. 「あげく」 is essentially treated the same as any noun. In other words, you would need the 「の」 particle to modify another noun.
「あげくの果て」 is ano