Do you want to say it or write it down? If you want to say it I don't think it is commonly used in everyday conversation:P I got two foreigner friends of mine who once said马马虎虎to me and at that time although I understood them but it was a little bit weird to me XD Cuz seldom do I say马马虎虎. But you can say还好instead of that. For example: —你喜欢画画吗？ —还好。 Or —你的中文很好！ —哈哈，还好，但是谢谢！我还需要努力^_^ By saying还好instead of马马虎虎people will your Chinese is much more Chinese and native! Hope it's helpful:))

马虎:mǎ hu 马马虎虎: mǎ mǎ hū hū 马: mǎ 虎:hǔ

马ma3虎hu 马ma2马ma3虎hu1虎hu1 其实我觉得拼音并不能表达出真正的发音！！！！！！

马虎 pronounce : mǎ hu 马马虎虎 pronounce ：mǎ mǎ hū hū Well, actually,马 pronounces mǎ and 虎 pronounces hǔ. But you know, Chinese is difficult and protean, it acquires some efforts. BTW, are learning Chinese?

马虎 ma3 hu1 马马虎虎 ma2ma3hu1hu1 when a third tone is followed by another third tone, the first one should be pronounced as a second tone. e.g. 你好 ni3hao3--->ni2 hao3, hen3hao3--->hen2 hao3