"Tomorrow will be 3 weeks that I have been working on this project" (means a continuous process that hasn't ended yet) Tomorrow will be 3 weeks since I have started working on this project (means a continuous process that hasn't ended yet) Is there a difference between "that" and "since" in these examples? Are they interchangeable?

"Since" vs "that"

English Language & Usage Asked by vick on August 20, 2021

"Tomorrow will be 3 weeks that I have been working on this project" (means a continuous process that hasn’t ended yet)
Tomorrow will be 3 weeks since I have started working on this project (means a continuous process that hasn’t ended yet)

Is there a difference between "that" and "since" in these examples? Are they interchangeable?

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