Q.What is the difference between "passage" and "safe passage" used in rule 8,9,10 and 18?

Not to impede Passage means not to come to a situation where risk of collosions arises and never to imepde passage; its like always the give away vessel. Fishing vessels are not supposed to fish in the traffic lanes and if they do they are always give away vessel

While for safe paaasage;  eg vessel less then 20 mtrs in the TSS  when coming from inshore traffic zone and situation comes where she is a stand on vessel in a crossing siutation with other power driven vessel like loaded VLCC and if it takes action that will land him in danger then sailing vessel should give safe passage to tanker or not to impede safe passage.

Hope I am correct.

Passage is what a vessel is following at the given time, i.e., the course being steered. Safe passage is based upon the margins of safety, and can the vessel remain with the margins of safety after making an alteration to avoid another vessel.  For example, a ship on a course of 040ºT is on her passage. If the same ship has a margin of safety of 3 miles either side, and she can take action and still stay within the margin of safety, her safe passage is within margins of safety. This reasoning can also be used for vessels within a TSS. 1. A vessel engaged in fishing is required to avoid impeding the passage of any vessel following the traffic lane. The vessel engaged in fishing is required to do so by allowing enough sea room for the vessel within the lane to be able to maintain her course, i.e., her passage. 2. A vessel of less than 20m in length or a sailing vessel is required to avoid impeding the safe passage of a power driven vessel following a lane. If the power driven vessel within the lane is able to take action and stay within the lane – her safe passage – the vessel less than 20m or sailing vessel may not have to take any action as long as there is no risk of collision or close quarters situation. If however, the power driven vessel within the lane has traffic around her and/or is in close proximity to other hazards and may not be able to alter, then her present course is her safe passage, and this should not be impeded.