Examples of phrases that are sometimes used in a sarcastic fashion include "thanks for the help," "great job," "take your time," "good luck with that" and "oh my God." Many sarcastic remarks, when written out, appear innocuous. However, such remarks are made sarcastic by the tone of voice that the speaker uses.
While "thanks for the help" is a common expression of gratefulness, the phrase can also take a sarcastic meaning to express frustration with someone who has messed something up instead of actually helping. "Great job" has a similar meaning in sarcasm, expressing the belief that nothing productive was actually done or said.
"Take your time," if said in a kind tone, is meant to comfort the listener if he is taking a long time to do something. However, in a sarcastic tone, it can be used to actually hurry someone up. "Good luck with that," while usually used to wish someone the best, is used in sarcasm to express doubt that someone actually completes his endeavor successfully. "Oh my God," a common expression of surprise in the English language, is used sarcastically in response to something wholly unsurprising. "What a surprise" is a phrase that is used in similar circumstances.