ing and noun eng

1. after my graduation
呢句係指係我嘅畢業典禮完結後
係可以話my friend and I will have a drink after my graduation.
意思係我同我朋友係畢業典禮完咗之後一齊去飲杯嘢~~

2.after my graduating
呢句句子嘅grammar應該有D問題,所以我都解釋唔到...

I'm so surprised you wanted to come. These tickets were pretty expensive. I didn't think you were into these sorts of things.

why use "didn't think you were into "?
成句句子大嘅意思係"我估唔到你會想黎, D票幾貴下, 我真係好驚喜。我冇諗過你會對呢方面有興趣。"

至於點解要用"didn't think you were into "，咁係因為句子中指我之前一直唔知你對呢D嘢有興趣，所以就要用past tense "didn't think"。"into"可以解作對...有興趣/着迷，所以you were into就解成你對...有興趣。

希望可以幫到你啦^^

After my graduation ...
After graduating ... (no my)

Below sentence is not properly written.
I'm so surprised you wanted to come. These tickets were pretty expensive. I didn't think you were into these sorts of things.
不知道你對這些活動感興趣，而且門卷也十分昂貴，得知你會參加這活動，感到很驚訝。

graduation 係一個名詞, 指「畢業」呢一件事/「畢業典禮」
graduating 係一個動名詞(gerund), 將graduate呢一個動詞名詞化......意思有少少唔同, 係講畢業呢一個動作, 通常係為左迎合句子裏面只能有一個verb既grammatical rule (sorry, 我唔記得左個agreement既名)而出現。ok, 先解釋名詞同動名詞既分別:

investment: 投資(資產)
investing: 投資呢個動作

I have a lot investment in China.
---我在中國有很多投資。
>>>這個「投資」是指資產/金額, 是可以量化的。

Investing in China is my most stupid decision ever!
---在中國投資是我一生最愚蠢的決定。
>>>指的是「投資」這個動作/行為。把invest in China 既invest 名詞化以切合文法。

而喺graduation/graduating呢個case, 兩者既意思分別不大, 一般來說, 我們都會用noun多於gerund, 因為gerund只指該「動作」, 而graduation這名詞同時可泛指畢業典禮。又例如:

After the graduation, we went to a party with all my friends.
---畢業典禮後, 我們一班朋友去了狂歡。

After graduating from the university, I got a job from a bank.
---畢業後, 我在銀行找到一份工作。
>>這裏是把graduate from the university呢一句既verb, graduate名詞化~

2013-06-06 13:44:25 補充：
當然, 你都可以
After my graduation, I got a job from a bank.

2013-06-11 12:44:50 補充：
OH~~
補充一點有關"didn't think you were into "的解說......

"I am into you"
(口語)我好鍾意/好冧你。

曾經有一齣電影/本書, 名為"He's just not that into you"
直解為「查實佢都唔係真係咁鍾意/咁冧你」

所以I didn't think you were into...... = I didn't think you like......
簡單來說, 在意思和用法上, 你可以如此理解: be into = like ~