Read each pattern and its example, then write your own sentence on the line.
〜に際して N + に際して／に際し；V-dict + に際して；N修飾は「に際しての + N」
Formal written or ceremonial phrasing meaning "on the occasion of / when doing." Marks a special, one-off moment such as a signing, departure or opening, not a routine event.
開会に際して、一言ごあいさつ申し上げます。 On the occasion of the opening, allow me to say a few words.
〜に当たって N + に当たって／に当たり；V-dict + に当たって；N修飾は「に当たっての + N」
Formal "upon / at the time of" for an important undertaking one is about to begin. Used in speeches and business writing; the main clause states what is done in preparation or in that spirit.
新社長は就任に当たって、抱負を述べた。 Upon taking office, the new president stated his aspirations.
〜に先立って N + に先立って／に先立ち；V-dict + に先立って；N修飾は「に先立つ + N」
Formal written "prior to," used when something is done in advance of a major event as a preliminary step. More restricted than 前に: the following event must be significant.
会議に先立って、資料が配られた。 Prior to the meeting, the materials were handed out.
〜において / 〜における N + において／においては／においても；N + における + N
Formal written replacement for で, marking a place, time, or field/domain. Common in reports, notices and academic writing; における modifies a following noun.
会議は第一会議室において行われます。 The meeting will be held in Conference Room 1.
〜にわたって / 〜にわたる N（期間・範囲）+ にわたって／にわたり；N + にわたる／にわたった + N
Formal expression for extent: something continues or spreads over a whole span of time, distance or range. The noun before it must express that span. にわたる modifies a noun.
会議は三時間にわたって続いた。 The meeting went on for three solid hours.
〜をめぐって N + をめぐって／をめぐり；N + をめぐる + N
"Concerning / surrounding," used for a topic that people argue, debate or compete over. Typical of news and formal writing; the main clause usually involves conflict or discussion.
新しい税制をめぐって議論が続いている。 Debate continues over the new tax system.