English term
Good rule of thumb
A good rule of thumb is to use at least two colourful foods in each menu.
Non-PRO (1): Tuncay Kurt
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Proposed translations
Türkiye
MEDICAL & PHARMACEUTICAL TRANSLATION
Native in: Turkish (Variant: Standard-İstanbul ) 
Works in: English to Turkish, Turkish to English
Temel kural olarak
Türkiye
It is all about what it really means.
Native in: Turkish (Variant: Standard-İstanbul )
Works in: English to Turkish, Turkish to English
iyi bir pratik kural
Mesela, bir binanın radye temel kalınlığı uzun mühendislik hesaplarıyla(statik ve dinamik) hesaplanır. Ama bir rule of thumb olarak 40 cm + kat adedi başına 10 cm ile kontrol edilebilir. Bu tarz kuralların tam sonucu vermediği ama belirli bir yanılma payı içerisinde sonuca yaklaştıkları tecrübe edilmiştir.
United States
Meticulous, scrupulous, curious work!
Native in: Turkish (Variant: Standard-İstanbul ) 
Works in: Turkish to English, English to Turkish, French to Turkish, and 1 more.
İyi bir temel kural
MITI, MCIL, DipTransIoLET
Native in: Turkish
Works in: English to Turkish, Turkish to English
Faydalı kurallardan biri
Bu birebir çevir isterseniz.
Fakat ben "... ması önerilir" şeklinde güzel bir Türkçe ile çevirirdim.
genel kabul görmüş iyi bir kural olarak
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Note added at 2 hrs (2014-04-19 09:22:09 GMT)
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Düzeltme: ...(hazırlayacağınız) her menüde en az iki renkli gıda kullanın.
Discussion
"İyi bir temel kural her menüde en az iki renkli gıdayı kullanmaktır."