你好 Last year I baught a chinese dictionary and I have started looking in it. I have found out that some words with same pinyin doesn't nessesserily got the same tone. So I wonder if I should go remembering how high the word starts, and if ji (downwards) could be said in 17 different ways; 寂计技伎妓寄冀觊季祭际系既记忌纪继 谢谢 for every feedback:)

In my opinion, you should associate the tone with the character/word you are dealing with. Some character's tone/pronunciation can change depending on the word they belong to. The way I do it: The characters you posted all use the 4th stone (falling tone).

寂寞，计算，技能，妓女，寄送，etc Exactly because so many words sound alike, modern Chinese favors two-character words. Above, I just added a second character frequently used with a character you listed.

I'm sorry for not responding any earlier guys. (Thought I would get some mail about any update on this topic via email). 谢谢 anyways:-)

Now you are confusing me! Aren't there just 4 different tones?

There are only 4 tones - 5 counting the neutral tone. The original post here gave the example of one combination of tone (4th tone)+spelling (ji)= jì and then 17 different characters that are pronounced in that combination=jì. Then, I expanded upon that by saying the relatively limited phonology in modern Mandarin results in speakers tending to use two character phrases to promote accuracy of communication, rather than using one character and have the meaning potentially be vague or confusing. Does this help?